Why Do I Need a Battery Anyway?

[gypsmjim]

Bear with me I'm still learning. Our old trailer was a 1964 and didn't have any of the newfangled gadgets.

When we leave camp Sunday night I disconnect the shore power, turn off the main battery switch and turn on the solar panel. When we return the next Friday night I reverse the procedure. The battery is always at 100%.

This week I made a switching error. I turned on the shore power and forgot to turn the battery switch on. I was surprised to see everything working with the battery isolated. I realize I have a converter, but I thought if the battery were disconnected it would leave an open circuit.

The trailer will never move, so I don't need any 12V power for brakes or whatever. So, when my current battery is no longer servicable, why should I bother replacing it?

[Wrascal]

I can see two reasons: First, in the event of a commercial power break, you'd still have some lights and second - come resell time the new owner will want to see it in place. I'd just install a cheap auto battery under those circumstances.

[Gman1372]

Your lights pump and slides are 12v amongst other things. Part of your thermostat/heat and refrigerator is 12v. Co detector is 12v. Stereo DVD player is 12v. Your power cord feeds your converter. Your converter feeds your 12v fixtures. Your solar panels will charge your battery to 100% but when you turn them off there's no draw. Can your panels keep up with usage when the switch is on, or when your using 12v power? Just a few questions in return

[Grumpy]

The battery also helps the converter function properly electronically.

[gypsmjim]

Originally Posted by Gman1372

Your lights pump and slides are 12v amongst other things. Part of your thermostat/heat and refrigerator is 12v. Co detector is 12v. Stereo DVD player is 12v. Your power cord feeds your converter. Your converter feeds your 12v fixtures. Your solar panels will charge your battery to 100% but when you turn them off there's no draw. Can your panels keep up with usage when the switch is on, or when your using 12v power? Just a few questions in return

This year we have a dedicated 120V service. The trailer is on our own private property. My panel was installed before we had shore power. Now, the panels are really redundant, because we are on shore power all the time.

[gypsmjim]

Originally Posted by Grumpy

The battery also helps the converter function properly electronically.

That sounds like a very good reason!

[Seann45]

Power goes off the fridge wont work... it needs a 12v source even on propane

[Dustdevil]

The battery is more than just a storage device. It also acts to absorb/attenuate any voltage spikes that may occur when large loads are suddenly shut off. It helps to keep voltage up when there are sudden large current draws applied to the system (turning on a blower motor, water pump, etc), and its there in case of any shore power loss. If you have ever seen your interior lights dim when you turn on the water pump, what you see is actually a sudden spike in current draw, which drops voltage somewhat. That would be far more pronounced if you had no battery in the system, and it would likely stress your power converter significantly to see such sudden surges on a daily basis. If your CO detector, smoke detector, are hardwired and operating on the 12 volt system, they don't like to see large swings in voltage. So, they would likely be negatively affected, and would at least start chirping every time the voltage swings a bit too low or high. Your tank level instruments likely would begin to malfunction, at least intermittently. All the 12 volt instruments could be affected eventually. It's a good idea to have at least a weak battery in the system pretty much all the time. Better if it's a battery in good working order.

[wags999]

If you ever tow your Rv again, you need a battery for the brake away device.